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Product Description
2.6.3
Winding and insulation system
The insulation materials we use ensure insulation class 155 (F) to EN 60034. Therefore, the winding temperature
rise may be max. 105 K at a coolant temperature of +40°C. We also use insulation materials with the temperature
profile TI 200 of class 180 (H) to increase the reliability of the motors.
The insulation system of the motors is designed such that they can be connected to an inverter with a maximum
DC link voltage U
U
link max.
to the inception voltage of the braking shopper or of the regenerative unit.
No mains
operation
2.6.4
Holding brake (optional)
The optional built-in holding brake is used to fix the motor shaft when the motor is at standstill or de-energized. It
is a permanent-field single-disc brake which operates on the closed-cicuit principle, i.e. the brake is effective when
the motor is de-energized, thus the motor shaft is held.
Holding brake
a working
Holding brakes are operated on DC current. The nominal voltage is 24 V. They can be connected to a central DC
voltage supply. Overvoltages, even transient, are not permitted since they deteriorate the permanent magnets ir-
reversibly. The excitation current ripple must be less than 20 % to ensure reliable opening of the brake and prevent
disturbing humming noises.
Motor rotation
in spite of an
active brake
If the excitation current of the holding brake is switched off on the DC side,
a voltage peak occurs which can be higher than 1,000 V. It is caused by the
inductance of the holding brake. A varistor should be connected in parallel to
the coil to prevent this voltage peak.
Attention ! On motors with plug connector and built-in brake, it is the user's
responsibility to install the varistor provided to control the brake.
GB - 12
= 840 V DC (constant 690 V DC).
link max.
is the maximum value of the DC link voltage which is only transient and approximately equivalent
The motors are not designed for direct connection to the three-phase system but
are to be operated via an electronic power inverter. Direct connection to the system
leads to the destruction of the motor.
Check the proper functioning of the brake (optional) after installing the motor. The
is not
optional holding brake is only designed for a limited number of emergency bra-
kings. The use as a working brake is not permitted.
brake
Since the holding brakes are permanent-magnet brakes, be sure to observe the
correct polarity of the DC voltage, otherwise the brake will not open.
Modern (field-oriented) frequency inverters are able to produce a high torque even
at low motor speeds. If the inverter has a sufficient current reserve, a multiple of the
rated motor torque can be produced. In this case the motor shaft may turn even if
the holding brakle is applied, because the holding torque of the brake is exceeded.
+
U
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